Do Now 10/5/11Do Now 10/5/11 Take out HW from last night.Take out HW from last night.

Text p. 62, #1-8 all, 13-20 all, 36-41 all, 56Text p. 62, #1-8 all, 13-20 all, 36-41 all, 56

Copy HW in your planner.Copy HW in your planner. Text p. 62, #9-12 all, 21-35 all, 50-53 allText p. 62, #9-12 all, 21-35 all, 50-53 all Quiz on integer addition and subtraction Friday.Quiz on integer addition and subtraction Friday.

In your journal, relate subtracting negative In your journal, relate subtracting negative numbers to a situation in real-life. Then give numbers to a situation in real-life. Then give an example. Solve your example using the an example. Solve your example using the “opp-opp.”“opp-opp.”

HomeworkHomework Text p. 62, #1-8 all, 13-20 all, 36-41 all, 56 Text p. 62, #1-8 all, 13-20 all, 36-41 all, 56

1) -31) -3 2) -112) -11 3) 63) 6 4) -64) -6 5) -45) -4 6) 56) 5 7) -107) -10 8) -108) -10 13) -513) -5 14) 414) 4 15) 815) 8 16) 1516) 15

17) 1217) 12 18) -1418) -14 19) 1619) 16 20) 020) 0 36) -636) -6 37) -1437) -14 38) -538) -5 39) -239) -2 40) -1340) -13 41) 241) 2 56) C56) C

ObjectiveObjective

SWBAT subtract integers using absolute SWBAT subtract integers using absolute values values

Section 2.3 Section 2.3 “Subtracting Integers” “Subtracting Integers”

When subtracting two integers, When subtracting two integers, ADD ADD the OPPOSITEthe OPPOSITE of the second of the second number to the first. number to the first.

-9 – 7 -9 – 7

-9 -9 + (-7)+ (-7) = =ADD the OPPOSITE “OPP-OPP”ADD the OPPOSITE “OPP-OPP”

-16-16

17 – 3317 – 3317 + (-33)17 + (-33)

|17| = 17|17| = 17 |-33| = 33|-33| = 33

33 – 17 33 – 17 = 16 = 16 - - Because 33 has a greaterBecause 33 has a greaterabsolute value than 17 the absolute value than 17 the answer is “negative”.answer is “negative”.

““Add the Opposite”Add the Opposite”

|-83| = 83|-83| = 83-83 + (+25)-83 + (+25)

|25| = 25|25| = 25

83 – 25 83 – 25 = 58= 58--Because 83 has a greaterBecause 83 has a greaterabsolute value than 25 the absolute value than 25 the answer is “negative”.answer is “negative”.

|53| = 53|53| = 53

53 + (-85)53 + (-85)

|-85| = 85|-85| = 85

85 – 53 85 – 53 = 32= 32Because 85 has a greaterBecause 85 has a greaterabsolute value than 53 the absolute value than 53 the answer is “negative”.answer is “negative”.

-83 – (-25)-83 – (-25) ““Add the Opposite”Add the Opposite”

53 – 8553 – 85 ““Add the Opposite”Add the Opposite”

--

Negative or Positive?Negative or Positive? Without solving the problem, decide whether the Without solving the problem, decide whether the

sum will be positive, negative, or zero. (HINT: sum will be positive, negative, or zero. (HINT: write the problem as a sum).write the problem as a sum).

17 – (-2)17 – (-2)

positivepositive

-13 – 11-13 – 11

negativnegativee

-14 – (-14)-14 – (-14)

zerozero

73 – 84 73 – 84 negativenegative

17 + (+2)17 + (+2)

-13 + (-11)-13 + (-11)

-14 + (+14)-14 + (+14)

73 + (-84) 73 + (-84)

Add the Opposite !!!Add the Opposite !!!

Try It Out…Try It Out…

-43 – 95-43 – 95= -138= -138

-43 – (-15)-43 – (-15) = -28= -28

37 – (-46)37 – (-46)= 83= 83

-123 – 162-123 – 162= -= -285285

13 – (-13)13 – (-13)= 26= 26

83 – 5783 – 57= 26= 26

-43 + (-95)-43 + (-95) -43 + 15-43 + 15

37 + 4637 + 46 -123 + (-162)-123 + (-162)

13 + 1313 + 13 83 + (-57)83 + (-57)

Evaluating Expressions with IntegersEvaluating Expressions with Integers

-6-6 – – 77-6 + (-7)-6 + (-7)

-13-13

x – yx – y x = -6 and x = -6 and y = 7y = 7

SubstituteSubstitute

““Opp-Opp”Opp-Opp”

Evaluating Expressions with IntegersEvaluating Expressions with Integers

-9-9 – – (-8)(-8)-9 + 8-9 + 8

-1-1

x – yx – y x = -9 and x = -9 and y = -8y = -8

SubstituteSubstitute

““Opp-Opp”Opp-Opp”

Real-Life ApplicationReal-Life Application A space shuttle has to endure extreme temperature A space shuttle has to endure extreme temperature

differences while traveling in outer space. When the differences while traveling in outer space. When the space shuttle is closer to the Sun it can be as hot as space shuttle is closer to the Sun it can be as hot as 3,000°F and when it travels far away from the Sun it can 3,000°F and when it travels far away from the Sun it can be as cold as -250°F. Find the difference in be as cold as -250°F. Find the difference in temperatures the space shuttle must endure.temperatures the space shuttle must endure.

3000 – (-250)3000 – (-250)

3000 + 2503000 + 250 ““Opp-Opp”Opp-Opp”

32503250The difference in temperatures the The difference in temperatures the

space shuttle must endure is 3,250 °Fspace shuttle must endure is 3,250 °F

““Integer” CardsInteger” Cards““Integer” CardsInteger” Cards RedRed cards = Negative cards = Negative BlackBlack cards = Positivecards = Positive Jack = 11, Queen = 12, King =13, Ace = 14 or 1.Jack = 11, Queen = 12, King =13, Ace = 14 or 1. Dealer deals each player 2 cards.Dealer deals each player 2 cards. The player with the The player with the higheshighest difference, gets all t difference, gets all

the cards from that round. the cards from that round. The player with the most cards at the end of the The player with the most cards at the end of the

deck wins!deck wins!

HomeworkHomework

Text p. 62, #9-12 all, 21-35 all, 50-53 allText p. 62, #9-12 all, 21-35 all, 50-53 all